Dzung Vu

Anatomy of the subtalar joint and imaging of talo-calcaneal coalition

Talo-calcaneal coalitions may be intra-articular or extra-articular in position and may be classified as fibrous, cartilaginous or osseous in morphology. Fibrous coalitions, particularly extra-articular talo-calcaneal coalitions, may have cross-sectional imaging findings that resemble normal anatomic variants, particularly the medial talo-calcaneal ligament and to a lesser extent the presence of an accessory articular facet between the posterior margin of the sustentaculum and postero-medial process of the talus. Typically, in the adult fibrous coalition, there will be some osseous deformity at the entheses, allowing differentiation from a medial talo-calcaneal ligament. The anatomy of the subtalar joint and its ligamentous supports, normal anatomic variations and their corresponding imaging appearance are reviewed in the first part of this article. In the second part, the various forms of talo-calcaneal coalition and their imaging appearance are reviewed.

Serotonergic neurons in the brainstem of the wallaby, Macropus eugenii.

The organisation and cytoarchitecture of the serotonergic neurons in a diprotodont marsupial were examined by using serial sections of the brainstem processed for serotonin immunohistochemistry and routine histology. The topographic distribution of serotonergic neurons in the brainstem of the adult wallaby (Macropus eugenii) was similar to that of eutherian mammals. Serotonergic neurons were divided into rostral and caudal groups, separated by an oblique boundary through the pontomedullary junction. Approximately 52% of the serotonergic neurons in the wallaby brainstem were located in the rostral midline nuclei (caudal linear nucleus, dorsal, median, and pontine raphe nuclei and the interpeduncular nucleus), whereas 21% were found in the caudal midline region (nuclei raphe magnus, obscurus, and pallidus). The remaining serotonergic neurons (27%) were located in more lateral regions such as the pedunculopontine tegmental nuclei, the supralemniscal nuclei (B9 group), and the ventrolateral medulla. The largest serotonergic group, the dorsal raphe, contained one‐third of the brainstem serotonergic neurons and showed five subdivisions, similar to that described in other species. In contrast, the median raphe did not show clear subdivisions. The internal complexity of the raphe nuclei and the degree of lateralisation of serotonergic neurons suggest that the wallaby serotonergic system is similar in organisation to that described for the cat and rabbit. This study supports the suggestion that the serotonergic system is evolutionally well conserved and provides baseline data for a quantitative study of serotonergic innervation of the developing cortex in the wallaby. J. Comp. Neurol. 411:535–549, 1999.

A preliminary anatomical basis for dual (uterosacral and sacrospinous ligaments) vaginal vault support at colporrhaphy

Introduction and hypothesisThis study aims to assess anatomically the likely effects of dual vaginal vault support using the uterosacral (USL) and sacrospinous ligaments (SSL) at colporrhaphy.MethodsObservations were made from 13 formalinized cadaver hemipelves to determine the vaginal vault support likely to be provided by traction on the (a) USLs and (b) the posterior vaginal vault towards the SSL.ResultsTraction on the USLs and SSLs both appeared to create a posterior and superior vector of vaginal vault tension, though that on the USLs appeared to be mainly on the anterior vaginal vault (and wall) with that on the SSL seemingly mostly on the posterior vaginal vault (and wall).ConclusionsConcomitant USL and SSL traction on the vaginal vault, now technically possible, appears, from these preliminary findings, to give complementary support to the anterior and posterior aspects of the vaginal vault and walls in a similar posterior and superior vector.

Use of laser 3D surface digitizer in data collection and 3D modeling of anatomical structures

A laser digitizer (Konica-Minolta Vivid 910) is used to obtain 3-dimensional surface scans of anatomical structures with a maximum resolution of 0.1mm. Placing the specimen on a turntable allows multiple scans allaround because the scanner only captures data from the portion facing its lens. A computer model is generated using 3D modeling software such as Geomagic. The 3D model can be manipulated on screen for repeated analysis of anatomical features, a useful capability when the specimens are rare or inaccessible (museum collection, fossils, imprints in rock formation.). As accurate measurements can be performed on the computer model, instead of taking measurements on actual specimens only at the archeological excavation site e.g., a variety of quantitative data can be later obtained on the computer model in the laboratory as new ideas come to mind. Our group had used a mechanical contact digitizer (Microscribe) for this purpose, but with the surface digitizer, we have been obtaining data sets more accurately and more quickly.

Determining the cross-sectional segmental anatomy of cadaveric human lungs.

An investigation of the complex boundaries between adjacent lobes and segments in human cadaveric lungs was undertaken to provide information for the later construction of a three‐dimensional model of the segmental and subsegmental anatomy of the human lungs. This was performed by analyzing scanned cross‐sections of the lungs after color‐coded gelatin had been injected into segmental bronchi and the lungs embedded in gelatin and frozen. The resulting images provided information regarding the pattern of boundaries present between both lobes and segments. Clin. Anat. 14:10–14, 2001.

Cross-Cultural Academic Experience in Medical Education: Enrichment of Teaching Through Confucian, French and American Influences

I was born in Vietnam, a country that had a strong Chinese cultural influence, and grew up at the transition between the French and American influence. I began teaching medical students in Vietnam when anatomy teaching was still influenced by the French philosophy and methods. I came to Australia as a refugee and returned to medical practice and resumed lecturing anatomy at the University of New South Wales where I have seen the changes from the traditional British-influenced programme to the new Problem-based method. I had previously completed my surgical training in the American system and recently had some teaching experience in North America as a visiting professor of anatomy. Thus I have been a student and lecturer in three different social and cultural environments (Confucian, French and American) prior to my current work as an academic in Australia. This chapter is an account of my observations and personal experience of the influence of cultural background on student-lecturer interactions.